The present invention relates to constant humidity evaporative wicking filter humidifier, and more specifically, to a humidifier of the type which is designed to satisfy home humidity requirements through the principle of evaporation of water into the air.
During the winter season, heated rooms normally tend to have low moisture conditions as a result of being filled with heated outside air. Low relative humidity causes many problems including discomfort to the occupants of the rooms, drying out of furniture and plants, excessive static electricity, and numerous problems. To overcome these problems, humidifiers are typically used to increase humidity levels within heated rooms during the winter heating season.
There are many different types and varieties of humidifiers that have been developed including centrifugal pump/evaporative filter humidifiers; air blown wicking/evaporative element humidifiers; motor driven belt pad humidifiers; wicking element humidifiers; and other types. The present invention is related to wicking element type humidifiers, but is principally constructed for use as a portable table top humidifier.
Several types of wicking element humidifiers are disclosed U.S. Pat. Nos. 4,822,533 and 4,865,775, which are assigned to the same assignee as the present invention. However, the wicking element humidifiers shown in these patents are principally, although not exclusively, used for floor mounted type humidifiers. The humidifier constructions shown in these patents disclose a humidifier which provides a constant evaporative area of a wicking element that is independently floatable on water within a reservoir tank, and which is part of a closed air flow path including a fixedly mounted fan, for discharging air with increased humidity from the humidifier. While constructions shown in these patents have worked quite well in floor-type models, they utilize more features and constructions than is necessary for portable table top humidifier constructions.
Other floor type humidifiers are known in which a wicking or evaporative element is at least in part submerged in a water bath and in which air is blown over the wetted wicking element so as to evaporate water therefrom. However, such immersed filter or wicking element humidifiers require a separate reservoir or water supply which feeds water to an evarporative sump by means of a float control valve in order to maintain a substantially constant water level wetting of the evaporative pad. Reference may be made to U.S. Pat. No. 2,031,055 for a more complete disclosure of such a humidifier.
Portable table top humidifiers have been disclosed in the prior art, such as in U.S. Pat. Nos. 3,188,007; 3,283,478; 3,290,021; and 4,699,737. In most cases, the portable table top humidifiers of the prior art have been principally used as vaporizers for users experiencing respiratory diseases. Unfortunately, most of the prior art portable table top humidifiers discharge relatively large water droplets or particles for inhalation by the person suffering from respiratory ailments. For vaporizers, the discharge of relatively large water droplets or particles does not present a problem; however, where it is desired to increase the humidity level throughout a particular room, the release of moist air in the form of vapor is desired, rather than water droplets or particles.
As a result, there is a recognized need for a portable table top humidifier which functions somewhat in the manner of the aforementioned floor-type models, but which is designed specifically for portable table top use, thus requiring a balancing of the construction, efficiency of operation and cost of such units. The construction of the constant humidity evaporative type wicking filter humidifier, as disclosed, can also be used for floor models, if desired.